This core provides adenovirus vectors for both in vitro and in vivo studies. Intraductal delivery resulting in transduction of mammary epithelial cells in the intact gland in the absence of inflammation has been extensively developed [26]. Although the majority of the experimental work that went into developing this system was conducted in the Neville laboratory, the McManaman laboratory has made extensive use of this technology during the present funding period. In the new proposal, all projects of plan to make use of this technology. A full list of the viruses currently available is presented in the Core Description.